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111.
Growth regulator induced movement of photosynthetic products into fruits of ;black corinth' grapes 总被引:3,自引:1,他引:2 下载免费PDF全文
The effect of exogenous growth regulators on movement of assimilates into flowers and young fruits of `Black Corinth' grapes was studied. Clusters were treated with growth regulator and after 0.5 hr to 5 days the leaves above the clusters were exposed to 14CO2. Control shoots received 14CO2 but no growth regulator. At harvest, counting and radioautographic techniques were used to ascertain amount and distribution of activity in clusters. Clusters were dipped in 4-CPA (4-chlorophenoxyacetic acid), GA3 (gibberellic acid), or BA (benzyladenine). All berries were heavier than controls within 3 days. Total counts in the fruits were increased by 4-CPA, and the distribution of radioactivity among the sugar, organic acid, and amino acid fractions was usually altered by all treatments. In a time series experiment, within 6 hr after treatment of fruits with GA3 there was almost an 8-fold increase in total counts relative to the control. After 12 hr there was about a 9-fold and 6-fold increase in counts in tartaric and malic acids, respectively, and in γ-aminobutyric acid, pipecolic acid, and valine increases of 56, 150, and 330%. Radioactivity in fructose was increased 70% in gibberellin-treated clusters over the controls. After 96 hr there were only about 1000 cmp per g fr wt in controls, but there were about 31,000 cpm counts in treated clusters. Treatment of clusters with gibberellin attracted less assimilates into the fruits when shoots had also been sprayed with gibberellin. Dipping portions of clusters in gibberellin increased the movement of 14C assimilates into the treated portions. Hormonal control of mobilization is discussed. 相似文献
112.
Summary The techniques of light and electron microscopy have been employed in a study of the protective coverings of the egg of Drosophila melanogaster. Data obtained during this investigation suggest the involvement of the follicle cells, in the production of one of these coverings and justify its classification as a secondary coat. The secondary coat of D. melanogaster is highly organized and has been divided into three Zones (I, II, IIII). The follicle cells enveloping the oocyte exhibit two phases of secretory activity each involving hypertrophy of the Golgi complex and rough endoplasmic reticulum, and the production of protein and polysaccharide components. The first phase concerns the elaboration of the material which gives rise to the homogeneous lamina referred to as Zone I. The second results in the release of an electron dense component which becomes organized into two laminae separated by struts or pillars; this construction is referred to as Zone II. At the completion of this secretory phase, the follicle cells assume a squamous morphology and a third Zone, composed of a homogeneous substance, appears between the follicle cells and Zone II.This investigation was supported by grant GM-08776 to one of us (EA) from the National Institutes of Health, United States Public Health Service. 相似文献
113.
The predictability of leucocyte typing in kidney transplantation was assessed by an analysis of 37 kidney transplants from sibling donors. Recipients who were identical for the HL-A antigens with their donors gave highly predictable results. In comparison with those siblings who were incompatible or compatible but not identical their grafts functioned earlier, they required less immunosuppression, and had never had any rejections. They also appeared to have less postoperative morbidity. These results indicate that less immunosuppression than is current in many transplant centres could well be used with benefit in HL-A identical sibling transplants. This could reduce the risk of infection and possibly minimize the adverse effects of steroids on wound healing in these patients. 相似文献
114.
115.
LOCALIZATION OF A BASIC PROTEIN IN THE MYELIN OF VARIOUS SPECIES WITH THE AID OF FLUORESCENCE AND ELECTRON MICROSCOPY 总被引:6,自引:3,他引:3 下载免费PDF全文
In this study, alanine was shown to be the N-terminal amino acid of a basic protein of low molecular weight that was isolated from either human or guinea pig brain. Antibodies prepared against the guinea pig protein were labeled with either fluorescein or ferritin. Studies with the labeled antibodies showed that an immunohistochemically similar protein is found in the myelin sheaths of central and peripheral nervous tissues of chicken and frog and a variety of mammalian species. Loss of integrity of the myelin during processing was shown to enhance markedly the antigen-antibody reaction. 相似文献
116.
117.
F. William Blaisdell Albert D. Hall Arthur N. Thomas Steven J. Ross 《The Western journal of medicine》1965,103(5):321-329
Three hundred patients with cerebrovascular occlusive disease have had cerebral angiographic examination at the Veterans Administration Hospital, San Francisco, in the last five years. The present technique consists of preliminary visualization of the aortic arch and the major extracranial branches, followed by selective study of the subclavian and carotid arteries as necessary for evaluation of the intracranial circulation.Nine major complications occurred (an over-all incidence of 3 per cent). Two patients died after angiography and seven had major neurologic deficits persisting for more than 24 hours. Three of these patients had permanent damage, but four recovered completely.One-third of the patients had extracranial disease and one-third had intracranial disease. No significant lesion was found in the remainder. In the 212 patients with lesions, multiple lesions were common, the average number being three. Six patients had brain tumors and five had aneurysms.The mechanism of the stroke could be ascertained readily in most of the patients, but the extent of the disease and the resulting symptoms varied considerably. Several patients with occlusion of most of the cerebral vessels had minimal symptoms, while others had catastrophic symptoms but only minimal findings at arteriography. 相似文献
118.
Eli Shapiro Steven D. Brown Alan R. Saltiel James H. Schwartz 《Developmental neurobiology》1991,22(1):55-62
In mollusks as in other animals, peptides can act as hormones, growth factors, and neurotransmitters. The presence of insulin in vertebrate brain as well as its actions on nerve cells led us to examine the electrophysiological effects of the mammalian hormone on Aplysia neurons. Application of insulin extracellularly causes hyperpolarization of L14 and L10, identified neurons of the abdominal ganglion. This hyperpolarization is associated with a decreased membrane conductance that reverses at ?35 mV. We also injected inositol phosphate glycan (IPG) into the identified neurons. This complex sugar, which was purified from rat liver and which is a putative second messenger for insulin in nonneural vertebrate cells (Saltiel and Cuatrecasas, 1986; Saltiel, Osterman, and Darnell, 1988), causes hyperpolarization with decreased membrane conductance in L14 and L10 similar to the effects of insulin. Furthermore, exposure of isolated ganglia to insulin results in the generation of IPG with a compensating decrease in its glycosyl-phosphatidylinositol precursor. We suggest that, in addition to its other roles, insulin may function as a neuropeptide transmitter using IPG as a second messenger. 相似文献
119.
Tumour cells possess the cell surface protease guanidinobenzoatase (GB) which can be located by the fluorescent probe 9-amino acridine (9-AA). Frozen sections and formaldehyde fixed sections of tumour tissue were used to demonstrate the interactions between GB, 9-AA and two protein inhibitors of GB. A cytoplasmic extract from the tumour tissue, and a purified inhibitor of plasminogen activator (PAI-1) were shown to be exchangeable components of the enzyme-inhibitor complex on the fixed tumour cell surfaces. The evidence suggests that GB is functionally very similar to plasminogen activator and that this enzyme can be regulated by protein inhibitors in vivo and also by changes in the redox potential at the cell surface. 相似文献
120.
Analysis of tomato DNA by pulsed field gel electrophoresis 总被引:2,自引:2,他引:0